Spreading the coffee in the portafilter is a step to take just before compacting the grind. Incorrectly done, this step can be the cause of bad extractions of your coffees. When you have more coffee on one side of the basket and you cup directly, it creates less dense areas, which will facilitate the passage of water.
Thus, a bad distribution of the coffee grounds before packing them contributes to an ignoble extraction of the nectar. To remedy this problem, there are some small tips. Some of them are little used in the professional world because they take time. Baristas will therefore be more likely to use accessories dedicated to this task.
In any case, it is essential to have the portafilter basket cleaned and dry before adding the grind. This in particular prevents the coffee sticks and adheres to the basket.
This is a method often used by people who fill the basket of the portafilter to the brim. With the finger, spread the coffee without packing it and expel the rest. I’m not a fan of this method, because I think we’re wasting coffee by applying it.
Tap the portafilter
Another method that does not require an accessory is to tap the portafilter on the worktop to break the mounted grounds. Then with your hand you tap on its sides (of the portafilter) to try to adjust the level. This method is the one I used at the beginning, it requires experience and is probably the longest and least effective.
One of the risks of this approach is to put coffee everywhere.
Weiss distribution technique
The use of a wooden toothpick or stalk to break the mounted grounds and spread the coffee grind into the basket is often coupled with a funnel. The funnel makes it possible to avoid getting out of the basket coffee by mixing with the toothpick. A funnel can be made by cutting the top of a plastic bottle or the bottom of a yoghurt pot at the right size. Below is a video to explain the process.
Coffee distributors are accessories created specifically to evenly spread the grounds in the basket. They are generally sold between 15 $ and 60 $ but can reach extremes as well as tampers (for example, the luxurious O.C.D. brand sells its distributors at 180 $).
You have to buy a coffee distributor that matches the diameter of your portafilter. Nevertheless, it is a rare accessory for certain sizes. For example, there are a lot of 58mm distributors, but the 57mm is much harder to find (and expensive).
For La Pavoni machines, as I explained for the tamper, I recommend a diameter of 51.5 mm for the coffee distributor. This extra half millimeter prevents coffee from remaining on the edges of the basket. A distributor of such a diameter is rare, I acquired mine for 40 € at BPlus, a company that I had already presented during my test of the coffee grinder Apollo.
It’s easy to use a coffee distributor. There are blades under the dispenser which turning will spread the coffee well in the basket. It is necessary to adjust the height of the dispenser (by screwing or unscrewing it, the rim of the dispenser abuts on the portafilter) so as not to pack the coffee. After evenly distributing the coffee, it remains to pack it with your tamper.
My impressions about the usefulness and the interest of such a tool are very positive. The simplicity, the speed of execution and the regularity of the result justify in my opinion its acquisition. I recommend however to choose a heavy accessory (about 450 to 550 g).
By applying one or other of these tips, the water will cross evenly the cake of coffee which will optimize your extractions.